Circuit interrupter control system



July 27, 1943. H. BANY 2,325,361

CIRCUIT INTERRUPTER CONTROL SYSTEMS Filed Aug. 2, 1941 Inventor Herman Bany,

H is Attorney Patented July 27, 1943 CIRCUIT INTERRUPTER CONTROL SYSTEM Herman Bany, Lansdowne, Pa., assignor to General Electric Company, a corporation of New York Application August 2, 1941, Serial No. 405,265

4 Claims. (Cl. 175-363) My invention relates to circuit interrupter control systems and particularly to systems for controlling the operation of circuit interrupters in a plurality of rectifying circuits through which current is supplied from an alternating current supply circuit to a direct current load circuit. My invention is particularly adapted for use in connection with polyphase vapor rectifiers which are provided with a plurality of circuit interrupters respectively in series with the anode circuits of the rectifiers and with means for effecting the opening of a circuit interrupter upon the occurrence of an arc-back involving the associated anode.

One object of my invention is to provide an arrangement of apparatus for controlling the operation of a plurality of circuit interrupters in a plurality of rectifying circuits such as the anode circuits of a polyphase vapor rectifier so that, when an arc-back occurs, it is extinguished as quickly as possible, and then the faulty rectifying circuits are restored to their normal operating conditions after the arc-back has been extinguished.

In accordance with my invention, the circuit interrupters associated with the anodes involved in an arc-back are opened as quickly as possible while the circuit interrupters, in series with the other anodes, remain closed. The opened 'circuit interrupters are then automatically reclosed to restore normal operating conditions. However, if, after a predetermined number of re closures, a circuit interrupter still iails to remain closed, all of the circuit interrupters in the other anode circuits are then opened to interrupt the supply of current through all or them in order not to overload the apparatus associated therewith.

My invention will be better understood from the following description when taken in connection with the accompanying drawing the single figure of which diagrammatically illustrates a circuit interrupter control system for a polyphase vapor rectifier, which embodies my invention, and the scope of my invention will be pointed out in the appended claims.

Referring to the drawing, 1 represents a polyphase vapor rectifier of any well known type for supplying direct current to a load circuit 2 from an alternating current supply circuit 3. As shown, the rectifier I has six anodes 4 which are connected respectively to the six terminals of a six-phase star connected secondary winding 5 of a transformer 6 the three-phase delta connected primary winding 1 of which is connected to the three-phase supply circuit 3. The nega tive side of the direct current load circuit 2 is connected to the neutral point of the secondary winding 5 of the transformer 6, and the positive side of the load circuit 2 is connected to the cathode 8 of the vapor rectifier I.

In series with each anode 4, I provide a separate circuit interrupter l0 which is arranged in any suitable manner so that it is quickly opened upon the occurrence of an arc-back involvin the associated anode 4 of the rectifier i. As shown, each circuit interrupter I0 is of the well known type comprising a holding coil ,which, when energized, magnetically holds the interrupter in its closed position against the bias of suitable opening means and a current cell H, which is so located with respect to the holding coil it that, when the current flow through the currentcoil l2 exceeds a predetermined value in a predetermined direction, the magnetic holding eiiect of the associated holding coil M is decreased sufficiently to allow the circuit interrupter to open. In the particular arrangement shown in the drawing the coils H and it of each circuit interrupter iii are so arranged that, when a power reversal occurs during an arc-back, the current in the current winding i2 is in the proper direction to decrease the holding eiiect produced by the associated holding winding ii. For closing the circuit interrupters iii, a common closing mechanism M is provided comprising a suitable motor i5 driving a separate operating means i 6 (shown as a cam) for each circuit interrupter. An operating circuit for the motor i5 is arranged to be completed whenever an associated control relay ii is energized. The motor l5 and the control relay iii are normally de-energized. The energizing circuit of the control relay H is controlled by another control relay i8 and suitable off-normal contacts l9 and 2B which are closed whenever the motor I5 is out of its normal position. In this manner the motor I5, whenever its operation is effected, effects a complete rotation of all of the cams l 6.

In accordance with my invention, I provide suitable automatic reclosing means for effecting the operation of the common closing motor l5 whenever any one of the circuit interrupters l0 opens so that the opened circuit interrupter is reclosed and for effecting a predetermined number of reclosures thereof in case the circuit interrupter fails to remain closed after each reclosure. Also means are provided for effecting the opening of all of the other circuit interrupters in case any of the circuit interrupters fails to remain closed after being reclosed a predetermined number of times.

In the particular arrangement shown in the drawing the automatic reclosing means comprises a timer 22 driven by a constant speed motor 23. When the timer 22 is in its normal position, it establishes a connection between a contact 26, which is connected to the normally opened parallel connected auxiliary contacts 25 on the circuit interrupters l0, and a contact 26, which is connected to the driving motor 23, so that the closing of any one of the auxiliary contacts 25 initiates the operation of the driving motor 23. As soon as the timer moves out of its normal position, it establishes a connection between the contact 26 and a contact 27 so that a locking circuit is completedfor the motor 23.

The timer 22 is provided with two sets of contacts 28 and 25 which are arranged to be closed successively as the timer is rotated with predetermined time intervals between successive closures thereof. When the contacts 28 are closed, a circuit is completed for a control relay 30 if at the same time themotor i is in its normal position and one or more of the circuit interrupters It are openso that the auxiliary contacts 26 thereof are closed. The relay 31?, when energized, completes a shunt circuit around the contacts 28 so that the relay 39 remains energized when these contacts 28 are subsequently opened by the timer. When the contacts 29 are closed and the relay 30 is energized, a circuit is completed for the control relay H to initiate the operation of the closing motor I5.

After the timer 22 has been in operation for a predetermined time and the contacts 28 and 29 have been closed a predetermined number of times, the timer 22 interrupts the connection between the contacts 26 and 21 in the energizing circuit of the driving motor 23 and establishes a connection between the contact 26 and a contact 32 which is connected to the series connected auxiliary contacts 33 of the circuit interrupters it so that, if all of the circuit interrupters are closed, an energizing circuit is then completed for the driving motor 23 to restore the timer 22 to its normal position. Also at the same time a connection is established between the contact 32 and a contact 35 which is connected to a control relay 35 so that this relay is also energized if all of the circuit interrupters iii are closed. The relay 35, when energized. establishes an energizing circuit for all of the holding coils H. Normally these holding coils H are energized through a set of contacts 35 which are connected together in all positions of the timer except in the lockout position thereof which is the position in which the contacts 26, 32 and 3a are connected together. Therefore, if any one of the circuit interrupters is open when the timer is in its lockout position, the holding coils H of all of the circuit interrupters iii are opened to eiiect the opening of all of the other circuit interrupters.

The, operation of the arrangement shown in the drawing is as'follows: 1

Under normal operating conditions, all of the circuit interrupters ID are closed so that each of the rectifying circuits through the rectifier I supplies direct current from the supply circuit 3 to the load circuit 2. The timer 22 is in its off position, which is the position in which it is shown. In this ofi position, the energizing circuits of the holding windings ll of all of the circuit interrupters iii are completed through the contacts 36 of the timer 22.

Whenever an arc-back occurs during the operation of the rectifier I, a reverse current flows through the anode t involved in the arc-back, and this reverse current efiects in a well known manner the opening of the circuit interrupter Iii through which the reverse current flows. The

opening of the auxiliary contacts 25 of the opened circuit interrupter i8 completes an energizing circuit for the driving motor 23 through the contacts 2t and 27 of the timer 22 so that the timer 22 starts to rotate. As soon as the timer 22 leaves its normal position, it disconnects the contact 26 from the contact 26 and connects it to the contact 2'! so that a holding circuit, which is independent of the contacts 25 of the circuit interrupters ill, is completed for the driving motor 23. for a predetermined time, it closes its contacts 28 and completes an energizing circuit for the control relay 30 through the auxiliary contacts 25 on the opened circuit interrupter i0 and the contacts 89 Which are closed when the closing motor i5 is in its normal position. The closing .of the contacts till of the relay 3!! completes a shunt circuit around the contacts 28 of the timer 22. When the timer '22 subsequently closes its contacts 29, an energizing circuit is completed for the control relay ill through the contacts at of the energized relay and the contacts 432 of the control relay it. The closing of the con acts d3 of the relay l7 completes a shunt circuit around the contacts ll of the relay 3t and the contacts 29 of the timer '22, and the closing of the con-' tacts M of the relay ll. completes an energizing circuit for the closing motor i5 so that the closing mechanism H1 is operated to reclose the open circuit interrupter l0. As soon as the closing motor l5 leavesits normal position, its auxiliary contacts 39 are opened and its auxiliary contacts 59 and 20 are closed. The opening of the contacts l9 interrupts the energizing circuit of the control relay 30 so that it becomes de-energized and cannot be energized again until the timer recloses its contacts 28. The closing of the contacts I9 completes a shunt circuit around the contacts c2 of the-relay i8 in the energizing circuit of the control relay H, and the closing of the contacts 20 completes an energizing circuit for the control relay it through the contacts 83 of the energizing control relay IT. The closing of the contacts Q5 of the control relay l8 completes a shunt circuit around the contacts 20. When the closing motor i5'has completed the closing of the opened circuit interrupter, which operation is completed long before the timer 22 again closes its contacts 28, the auxiliary contacts 39 are reclosed and the auxiliary contacts is and 20 are opened. The opening of the contacts it interrupts the energizing circuit of the control relay it which, by opening its contacts 63, efiects thesubsequent de-energization of the control relay it.

If a circuit interrupter it opens immediately after it is reclosed by the closing mechanism 48, the timer 22, by successively closing its contacts 28 and 29, again eflects in the manner above described subsequent reclosures of the circuit interrupter at predetermined time intervals after each previous reclosure. If, however, the circuit interrupter remains closed after any reclosure, the subsequent closing of the contacts 28 and 29 of the timer 22 does not effect an operation of the closing mechanism is because the energizing After the timer 22 has been in operation all of the circuit interrupters 16 are closed when the timer 22 reaches its lockout position, a circuit is completed for the control relay 35 through the contacts 32 and 34 of the timer. The closing of the contacts 38 of the control relay 35 completes the energizing circuits forthe holding coils H of the circuit interrupters l6 so that these holding coils are not de-energized by the timer opening its set of contacts 36 when it is in its lockout position. Also a circuit is completed for the driving motor 23 through the timer contacts 26 and 32 and the series connected contacts 33 of all of the circuit interrupters l0 so that the timer is moved out of its lockout position. As soon as the timer moves out of its lockout position, the

contacts 36are again closed to re-establish the energizing circuits for the holding coils II, and the contacts 26 and 21 are again connected together so that the timer 22 is restored to its normal position,

If any one of the circuit interrupters I6 is 'open when the timer 22 reaches its lockout position, the series circuit through the contacts 33 of the circuit interrupters is open so that the above traced energizing circuit of the control relay 35 is not completed in the lockout position of the timer. Therefore, when the timer opens the circuit through its contacts 36, all of the holding coils H are de-energized so that all of the circuit interrupters I6 open to disconnect the rectiher I from the secondary winding 5 of the transformer 6. Also the operating circuit for effecting the operation of the driving motor 23 to move the timer 22 out of its lockout position is not completed.

Therefore, it will be seen that I have provided an arrangement which, in case of an arc-back, tries several times to re-establish service through the faulty rectifying circuit while maintaining service through the other rectifying circuits and interrupts all of the rectifying circuits in case service cannot be restored through the faulty rectifying circuit.

While I have, in accordance with the patent statutes, shown and described my invention as applied to a particular system and as embodying various devices diagrammatically indicated, changes and modifications will be obvious to those skilled in the art, and I therefore aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In combination, a vapor rectifier comprising a plurality of anodes, an individual circuit interrupter in series with each anode, and means responsive to a reversal of power through an anode for automatically opening and reclosing a predetermined number of times within a predetermined time interval the circuit interrupter in series with the anode through which the power reversal occurs and for opening all of the other circuit interrupters if the circuit interrupter in series with the anode through which the power reversal occurs is open at the expiration of said predetermined time interval.

2. In combination, a direct current circuit, an alternating current circuit, rectifying means supplying current'from said alternating current circuit to said direct current circuit comprising a plurality of rectifying circuits, individual circuit interrupting means in each rectifying circuit, and means responsive to a reversal of power in a rectifying circuit for automatically opening and reclosing a predetermined number of times within a predetermined time interval the circuit interrupter in series with the anode through which the power reversal occurs and for opening all of the other circuit interrupters if the circuit interrupter in series with the anode through which the power reversal occurs is open at the expiration of said predetermined time interval.

3. In combination, a vapor rectifier comprising a plurality of anodes, an individual circuit interrupter in series with each anode, means responsive to a reversal of power through an anode for opening the circuit interrupter in series therewith, a common closing mechanism for all of said interrupters, and means responsive to the opening of an interrupter for effecting the operation of said closing mechanism.

4. In combination, a vapor rectifier comprising a plurality of anodes, an individual circuit interrupter in series with each anode, means responsive to a reversal of power through an anode for opening the circuit interrupter in series therewith, a common closing mechanism for all of said interrupters, and means responsive to the opening of an interrupter for efiecting the operation of said closing mechanism a predetermined number of times and for opening all of the other circuit interrupters after a circuit interrupter has biegn reclosed said predetermined number of t es.

HERMAN BANY. 

